Question

7a. a person who has lactose intolerance can drink lactose - free milk without symptoms. this allows them to benefit from the protein, calcium and vitamin d that milk provides. explain how a manufacturer can use lactase to produce lactose - free milk.
7b. do you think lactose - free milk contains glucose?

Explanation:

7a.

Lactase is an enzyme. Enzymes are biological catalysts that speed up chemical reactions. Lactose is a disaccharide sugar in milk. The reaction catalyzed by lactase is the hydrolysis of lactose. The chemical formula for lactose is \(C_{12}H_{22}O_{11}\). The hydrolysis reaction of lactose using lactase is \(C_{12}H_{22}O_{11}+H_{2}O\stackrel{lactase}{\longrightarrow}C_{6}H_{12}O_{6}(glucose)+C_{6}H_{12}O_{6}(galactose)\). So, a manufacturer can add lactase to milk. The lactase will catalyze the breakdown of lactose (the sugar that causes problems for lactose - intolerant people) into glucose and galactose. This results in lactose - free milk.

As shown in the hydrolysis reaction of lactose (\(C_{12}H_{22}O_{11}+H_{2}O\stackrel{lactase}{\longrightarrow}C_{6}H_{12}O_{6}(glucose)+C_{6}H_{12}O_{6}(galactose)\)) in part 7a, when lactose is broken down by lactase, glucose is one of the products.

Answer:

A manufacturer can add lactase to milk. Lactase catalyzes the hydrolysis of lactose (\(C_{12}H_{22}O_{11}+H_{2}O\stackrel{lactase}{\longrightarrow}C_{6}H_{12}O_{6}(glucose)+C_{6}H_{12}O_{6}(galactose)\)), breaking it down into glucose and galactose, thus producing lactose - free milk.

7b.